Changes in the prevalence of asthma and related risk factors in adolescents: Three surveys between 1994 and 2015.

METHODS: This study assesses the temporal trend of current asthma symptoms prevalence and associated factors in Chilean adolescents from South-Santiago, considering surveys performed in 1994, 2002 and 2015. RESULTS: The prevalence of current asthma symptoms showed a trend to increase from 11.1% in 1994 to 13.4% in 2015 (p<0.001); physician-diagnosed asthma increased from 11.5% to 13.8%, (p<0.001) whereas severe asthma and asthma with exercise decreased (p<0.001). Female adolescents had a higher prevalence of current asthma in the three surveys (p<0.001), and was a risk factor for asthma in the three surveys. In 2002, frequent consumption of meat and potatoes were associated with current asthma while frequent vigorous exercise was protective. Frequent exercise and parental tobacco smoking were risk for asthma in 2015 (p<0.001). Current active tobacco smoking showed a trend to increase reaching a prevalence of 28.9% in 2015 (p<0.001). There was a consistently low proportion of adolescents with current wheezing and asthma diagnosis (32.1% in 2015) and 37.6% of them had no asthma treatment. CONCLUSION: The prevalence of current asthma in adolescents from the studied area would be still increasing. As in other studies, female adolescents had a higher prevalence of current asthma. Current active tobacco smoking has strikingly increased in the studied children while indoor passive tobacco exposure remains inadmissibly high. Our findings suggest that asthma in children is underdiagnosed and undertreated. More attention should be given to female gender, tobacco exposure, air pollution and local diagnostic preferences when studying and interpreting trends of asthma prevalence in adolescents from developing localities.

Risk factors for recurrent wheezing--International Study of Wheezing in Infants (EISL) phase 3.

BACKGROUND: We aimed to identify factors associated with recurrent wheezing (RW) in infants in the first year of life living in the Southern region of São Paulo city and participating in the "Estudio Internacional de Sibilancias en Lactantes (EISL)" - phase 3 (P3). METHODS: 1335 parents of infants who were attended in primary care health units in the Southern region of São Paulo city from 2009 to 2010 answered the EISL-P3 written questionnaire. The wheezing group was stratified in accordance to the frequency of wheezing episodes as occasional wheezing (OW, less than three episodes), or RW (three or more episodes). Wheezing-associated factors were evaluated using multivariate analysis and were expressed as odds ratio (OR) and 95% confidence interval (95%CI). RESULTS: The most relevant factors related to OW were pneumonia (OR=3.10, 95%CI=1.68-5.73), hospitalisation due to pneumonia (OR=2.88, 95%CI=1.26-6.56) and recurrent upper respiratory infection (URI, OR=1.87, 95%CI=1.25-2.81). Regarding RW, recurrent URI (OR=5.34, 95%CI=3.83-7.45), pneumonia (OR=4.06, 95%CI=2.87-5.74) and asthmatic siblings (OR=3.02, 95%CI=1.67-5.45) were the most significantly associated factors. CONCLUSIONS: In the present study, we found that recurrent URI, positive history of pneumonia and familiar history of asthma were the most relevant factors associated with RW. The precocious knowledge of these factors can enable the identification of the probable asthmatic infants and can improve both prevention strategies and treatment of these patients.

Effect of once-daily generic ciclesonide on exhaled nitric oxide in atopic children with persistent asthma.

BACKGROUND: Ciclesonide (CIC) is an effective inhaled corticosteroid for treating asthmatic children. However, its effect on airway inflammation assessed by the fraction of exhaled nitric oxide (FENO) in children with persistent asthma is virtually unknown. We aimed to assess the effect of once-daily generic CIC, 80 or 160 µg, on FENO, lung function, asthma control and bronchial hyperresponsiveness, in atopic children with persistent asthma. METHODS: This was a 12-week, randomised, double-blind, parallel-group study. Sixty children with mild-to-moderate persistent asthma were recruited. Changes in FENO, asthma control score, lung function (FEV1) and bronchial hyperresponsiveness to methacholine (BHR) were used to assess the effects of both CIC doses. Non-normally distributed variables were log-transformed to approximate normality, and parametric tests were used for comparisons within and between groups at baseline and after 12 weeks of treatment. RESULTS: In the CIC 80 µg group, FENO decreased from 45.0 ppb (95% CI 37.8-53.7) to 32.7 ppb (95% CI 21.0-47.3) at the end of study (P=0.021), whereas in the CIC 160 µg group, FENO decreased from 47.3 ppb (95% CI 40.4-55.3) to 30.5 ppb (95% CI 24.1-38.7) (P<0.001). The difference between groups in FENO at the end of study was not significant (P=0.693). There was a significant improvement of asthma control with both CIC doses but there was no significant change in BHR or FEV1 in either group. CONCLUSION: Once-daily generic ciclesonide (80 µg or 160 µg), for 12 weeks, is effective to improve airway inflammation and asthma control in atopic children with persistent asthma.

Factors associated to recurrent wheezing in infants under one year of age in the province of Salamanca, Spain: Is intervention possible? A predictive model.

OBJECTIVES: Wheezing is a very common problem in infants in the first months of life. The objective of this study is to identify risk factors that may be acted upon in order to modify the evolution of recurrent wheezing in the first months of life, and to develop a model based on certain factors associated to recurrent wheezing in nursing infants capable of predicting the probability of developing recurrent wheezing in the first year of life. METHODS: The sample was drawn from a cross-sectional, multicentre, descriptive epidemiological study based on the general population. A total of 1164 children were studied, corresponding to a questionnaire response rate of 71%. The questionnaire of the Estudio Internacional de Sibilancias en Lactantes (EISL) was used. Multiple logistic regression analysis was used to estimate the probability of developing recurrent wheezing and to quantify the contribution of each individual variable in the presence of the rest. RESULTS: Infants presenting eczema and attending nursery school, with a mother who has asthma, smoked during the third trimester of pregnancy, and did not consume a Mediterranean diet during pregnancy were found to have a probability of 79.7% of developing recurrent wheezing in the first year of life. In contrast, infants with none of these factors were seen to have a probability of only 4.1% of developing recurrent wheezing in the first year of life. These results in turn varied according to modifications in the risk or protective factors. CONCLUSIONS: The mathematical model estimated the probability of developing recurrent wheezing in infants under one year of age in the province of Salamanca (Spain), according to the risk or protective factors associated to recurrent wheezing to which the infants are or have been exposed.

Siblings, asthma, rhinoconjunctivitis and eczema: a worldwide perspective from the International Study of Asthma and Allergies in Childhood.

BACKGROUND: Associations of larger families with lower prevalences of hay fever, eczema and objective markers of allergic sensitization have been found fairly consistently in affluent countries, but little is known about these relationships in less affluent countries. METHODS: Questionnaire data for 210,200 children aged 6-7 years from 31 countries, and 337,226 children aged 13-14 years from 52 countries, were collected by Phase Three of the International Study of Asthma and Allergies in Childhood (ISAAC). Associations of disease symptoms and labels of asthma, rhinoconjunctivitis and eczema were analysed by numbers of total, older and younger siblings, using mixed (multi-level) logistic regression models to adjust for individual covariates and at the centre level for region, language and national affluence. RESULTS: In both age groups, inverse trends (P < 0.0001) were observed for reported 'hay fever ever' and 'eczema ever' with increasing numbers of total siblings, and more specifically older siblings. These inverse associations were significantly (P < 0.005) stronger in more affluent countries. In contrast, symptoms of severe asthma and severe eczema were positively associated (P < 0.0001) with total sibship size in both age groups. These associations with disease severity were largely independent of position within the sibship and national GNI per capita. CONCLUSIONS: These global findings on sibship size and childhood asthma, rhinoconjunctivitis and eczema suggest at least two distinct trends. Inverse associations with older siblings (observations which prompted the 'hygiene hypothesis' for allergic disease) are mainly a phenomenon of more affluent countries, whereas greater severity of symptoms in larger families is globally more widespread.

Fraction of exhaled nitric oxide in healthy Chilean schoolchildren aged 8-15 years.

BACKGROUND: The fraction of exhaled nitric oxide (FENO) measured using portable devices is increasingly used in the clinical setting to assess asthmatic children. However, there is little and variable information on the reference values obtained using these devices in healthy children from different populations. METHODS: 190 healthy non-smoker children (8-15 years old) were randomly selected from public schools participating in this study. The objective was to determine FENO reference values for healthy Chilean schoolchildren. Healthy individuals were identified by medical interview and parent questionnaire on the use of asthma medications, and current and past symptoms of asthma, rhinoconjunctivitis and eczema. FENO was measured at schools using a portable device with electrochemical sensor (NIO MINOX). Reference values of FENO were expressed as geometric mean and upper limit of the 95% reference interval (right-sided). The relationship of FENO with gender, age, height, body mass, and other factors was assessed by multiple regression, and the difference between groups was contrasted by ANOVA. RESULTS: The FENO geometric mean was 15.4ppb with a 95% reference interval upper limit (right-sided), of 27.4ppb (90%CI 25.6-29.2). The 5th and 95th percentiles were 9.0ppb and 28.0ppb, respectively. Height was the only factor significantly associated to FENO (p=0.022). There was no significant difference in mean FENO regarding age, gender, weight, parent reported rhinoconjunctivitis and eczema. CONCLUSION: This study suggests that FENO values higher than 27ppb are likely to be abnormal and would reflect airway inflammation in children as those in the present study.

Gender differences in the relationship between body mass index (BMI) changes and the prevalence and severity of wheezing and asthma in the first year of life.

BACKGROUND: Rapid weight gain has been recently associated with asthma at school age, but its influence in respiratory symptoms during infancy is still unknown. METHODS: Answers from 6541 parents living in six different cities of Brazil to the International Study of Wheezing in Infants (EISL) questionnaire were analysed. Data from reported weight and height at birth and at one year were used to calculate BMI. Rapid body mass index (BMI) gain was defined by the difference in BMI superior to 1.0z and excessive by the difference superior to 2.0z. RESULTS: Rapid BMI gain was found in 45.8% infants and excessive in 24.4%. Boys showed a significantly higher BMI gain than girls. Girls with rapid BMI gain showed a significantly higher prevalence of hospitalisation for wheezing (8.8% vs. 6.4%; aOR: 1.4, 95%CI: 1.1-1.8), severe wheezing (18.1% vs. 15.0%; aOR: 1.3, 95%CI: 1.0-1.5) and medical diagnosis of asthma (7.5% vs. 5.7%; aOR: 1.3, 95%CI: 1.0-1.7). Girls with excessive BMI gain also had a significantly higher prevalence of hospitalisation for wheezing (9.8% vs. 6.7%; aOR: 1.5, 95%CI: 1.1-2.0) and severe wheezing (18.9% vs. 15.5%; aOR: 1.3, 95%CI: 1.0-1.6). No significant association was found among boys. CONCLUSIONS: The majority of the evaluated infants showed BMI gain above expected in the first year of life. Although more commonly found in boys, rapid and excessive BMI gain in the first year of life was significantly related to more severe patterns of wheezing in infancy among girls.

Postoperative care in hypospadias. Common practices and evidence available. / Cuidados postoperatorios en el hipospadias. Prácticas habituales y evidencia disponible.

INTRODUCTION: There are many alternatives available regarding postoperative care in hypospadias surgery. The objective of this study was to assess the current care situation in our environment and to review the evidence available for pediatric surgeons who conduct this procedure. MATERIALS AND METHODS: A survey regarding the main aspects of hypospadias postoperative care was created and distributed to pediatric surgeons. In addition, the evidence currently published in this field was reviewed. RESULTS: A total of 46 replies were achieved. 100% of the surgeons leave in place a probe or stent, and more than 80% remove it after 5 or 7 days. 87.8% of the respondents use a double diaper, but only 65.2% discharge patients early in the postoperative period. 60.9% prescribe antibiotic prophylaxis for as long as the probe remains in place, and 34.8% use full-dose antibiotic therapy. DISCUSSION: There was a general consensus regarding urethroplasty guiding and the use of compression dressings among the pediatric surgeons surveyed. However, more discrepancies were found in the use of antibiotic therapy and early discharge. The currently available evidence and international practice suggest using a probe with double diaper and early discharge, with postoperative antibiotics being limited. In the absence of clear evidence for a specific care type, the patient's experience could be used to choose the best postoperative protocol on an individual basis.

INTRODUCCION: Existen numerosas alternativas en lo que respecta a los cuidados postoperatorios en la cirugía de hipospadias. El objetivo de este estudio es evaluar la situación actual de estos cuidados en nuestro medio y revisar la evidencia existente al respecto para cirujanos pediátricos que realizan este tipo de intervenciones. MATERIAL Y METODOS: Hemos elaborado y distribuido una encuesta que recoge los principales puntos en el cuidado postoperatorio del hipospadias dirigida a cirujanos pediátricos. Se ha realizado revisión de la evidencia actual publicada al respecto en la especialidad. RESULTADOS: Hemos obtenido un total de 46 respuestas. El 100% de los cirujanos dejan algún tipo de sonda o stent y más del 80% están de acuerdo en retirarlo tras 5 o 7 días. El 87,8% de los encuestados utiliza el doble pañal, pero solo el 65,2% da alta precoz en el postoperatorio. Un 60,9% pauta profilaxis antibiótica mientras dure el sondaje y un 34,8% antibioterapia a dosis plenas. DISCUSION: Existe consenso general respecto a la tutorización de la uretroplastia y el uso de apósito compresivo entre los cirujanos pediátricos encuestados. Se detectan más discrepancias en el uso de antibioterapia y el alta precoz. La evidencia actual y la práctica a nivel internacional apunta hacia el uso de la sonda a doble pañal con alta precoz y la limitación del uso de antibióticos postoperatorios. En ausencia de clara evidencia que favorezca un tipo de cuidado u otro, la experiencia del paciente podría ser utilizada para elegir el mejor protocolo postoperatorio individualizado.

The International Study of Asthma and Allergies in Childhood (ISAAC) Phase Three: a global synthesis.

This ISAAC Phase Three synthesis provides summarised information on the main findings of the study, regional tables and figures related to the prevalence and severity of current symptoms of asthma, rhinoconjunctivitis and eczema in the main regions of the world. The large number of surveyed children (≈1,200,000), the large number of centres (233) and countries (98) that participated in ISAAC Phase Three makes this study the most comprehensive survey of these diseases ever undertaken. Globally, the prevalence for current asthma, rhinoconjunctivitis and eczema in the 13-14-year age group was 14.1%, 14.6% and 7.3%, respectively. In the 6-7-year age group the prevalence for current asthma, rhinoconjunctivitis and eczema was 11.7%, 8.5% and 7.9%, respectively. The study shows a wide variability in the prevalence and severity of asthma, rhinoconjunctivitis and eczema which occurs not just between regions and countries but between centres in the same country and centres in the same city. This study definitively establishes that the prevalence of those diseases can be very high in non-affluent centres with low socioeconomic conditions. The large variability also suggests a crucial role of local environment characteristics to determine the differences in prevalence between one place and another. Thus, ISAAC Phase Three has provided a large body of epidemiological information on asthma, rhinoconjunctivitis and eczema in childhood from contrasting environments which is expected to yield new clues about the aetiology of those conditions and reasons for their marked global variability.

Natural occurrence of lethal aspergillosis in the cattle tick Rhipicephalus (Boophilus) microplus (Acari:Ixodidae).

The purpose of this study was to describe an unreported entomopathogenic fungus that naturally infects the cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae). Engorged female ticks, showed symptoms of fungal infection after controlled tick infestation of cattle. Infected ticks developed a distinctive dark colour, a pale mould grew over the cuticle and the ticks eventually died covered with fungal conidiophores. The responsible fungus was isolated and cultured on mycological medium and submitted to microscopic morphology, biochemical phenotyping and 18S rRNA ribotyping analyses, which identified it as aflatoxin-producing Aspergillus flavus. Spores from the cultured fungus were experimentally sprayed over healthy engorged female ticks, obtaining an 80% prevalence of experimental infection of healthy ticks and their egg masses, the larval progeny after incubation under laboratory conditions was also infected. These results demonstrate that A. flavus is the causative agent of the natural fungal disease of the cattle tick R. microplus described here.

Intestinal duplication isolated from the digestive tract: an entity to be considered. / Duplicación intestinal aislada respecto al tracto digestivo: una entidad a tener en cuenta.

OBJECTIVES: To review intestinal duplications isolated from the digestive tract. MATERIAL AND METHODS: Description of the 27 isolated intestinal duplication cases published; presentation of a new case. RESULTS: Intestinal duplication isolated from the digestive tract represents an extremely rare malformation. This type of duplication is not in close contact with any segment of the intestinal tract, and it has its own vascular pedicle. Preoperative diagnosis rates are lower than those found in classic duplications. In addition to the potential complications, malformation torsion is also to be considered. CONCLUSIONS: This infrequent variant is to be considered at differential diagnosis. Potential torsion should also be taken into account in order to decide when an asymptomatic patient should undergo surgery.

OBJETIVOS: Revisión de las duplicaciones intestinales aisladas, sin conexión con el tracto digestivo. MATERIAL Y METODOS: Se recopilan los 27 casos de duplicación intestinal aislada publicados hasta el momento y se presenta un nuevo caso. RESULTADOS: Las duplicaciones intestinales aisladas sin conexión con el tracto digestivo representan una variante de la malformación extremadamente rara. Este tipo de duplicaciones no están en contacto íntimo con ningún segmento del tracto intestinal y cuelgan de un pe­dículo vascular propio. Tienen menos tasa de diagnóstico prequirúrgico que las duplicaciones clásicas y a las posibles complicaciones hay que añadir la torsión de la malformación. CONCLUSIONES: Es interesante conocer esta variante infrecuente para considerarla en el diagnóstico diferencial. La posibilidad añadida de torsión debe tenerse en cuenta para decidir el momento de la cirugía en el paciente asintomático.

Increased oxidative stress in children with post infectious Bronchiolitis Obliterans.

BACKGROUND: There is increasing evidence that oxidative stress is involved in the development and severity of bronchiolitis obliterans occurring in post-transplant patients. In developing countries, the most common form of bronchiolitis obliterans occurs after severe lung infection, mainly caused by adenovirus. However, the oxidative status in the lungs of children with post infectious bronchiolitis obliterans is unknown. METHODS: The aim of this study was to measure the oxidant (8-isoprostane and protein carbonyls) and antioxidant (catalase and glutathione peroxidase) activity in the bronchoalveolar lavage fluid of 21 children with post-infectious bronchiolitis obliterans, and to correlate oxidant/antioxidant level with lung function. Lung function was assessed by spirometry and plethysmography, one week prior to fiberbronchoscopy. RESULTS: There was a markedly increased oxidative stress (lipid and protein oxidation) in the bronchoalveolar lavage fluid, and a notorious impairment of lung function demonstrating moderate-severe distal airway narrowing. There was not a significant correlation between the level of oxidants or antioxidants and lung function. There was a consistent antioxidants/oxidants pattern characterised by markedly increased 8-isoprostane and carbonyls, increased GPx and normal catalase activity. CONCLUSION: The present study shows for the first time that children with post-infectious bronchiolitis obliterans have a markedly increased oxidative stress in their lungs.

[Value of the direct cystoscintigraphy in the diagnosis of vesicoureteral reflux in patients with prenatal hydronephrosis]. / Valor de la cistogammagrafía directa en el diagnóstico del reflujo vesicoureteral en pacientes con hidronefrosis prenatal.

OBJECTIVE: As the radiation received in conventional cystography is about 20 times higher than radionuclide cystography and the sensitivity of the last is higher in order to diagnose vesicoureteral reflux, we consider the use of radionuclide cystography in early detection of reflux in patients with prenatally detected hydronephrosis. MATERIALS AND METHODS: Between 2003 and 2009, a study of neonates with prenatal history of hydronephrosis was performed in order to rule out reflux. Our protocol was as follows: The diagnosis was confirmed by postnatal ultrasound at 1 week (in this case patient initiate antibiotic prophylaxis). A new ultrasound was repeated at 6 weeks, if the dilatation was larger than 8 mm at this time, direct radionuclide scintigraphy was performed. The patients were placed on prophylactic antibiotics until the screenining results were known. Conventional cystography was performed if a male infant showed severe dilatation, or in general in cases with parenchymatous atrophy or if a duplex system was suspected. RESULTS: In 13 (20%) of the 65 cases (18 kidneys) reflux was detected (3 minor, 8 moderate and 7 severe). In most cases, follow up was performed with radionuclide cystography. None of the patients with reflux placed on prophylactic antibiotics developed a febrile urinary tract infection during the first year of life. CONCLUSIONS: Direct radionuclide cystography is a useful diagnostic method in early detection of vesicoureteral reflux in patients with prenatal hydronephrosis with higher sensitivity than conventional cystography, and with an important advantage concerning radiation of the patient. Patients screened and placed on prophylactic antibiotics are probably going to present less episodes of pielonephrytis.

Prevalence of symptoms of eczema in Latin America: results of the International Study of Asthma and Allergies in Childhood (ISAAC) Phase 3.

BACKGROUND: The aim of the International Study of Asthma and Allergies in Childhood (ISAAC) was to evaluate the prevalence of symptoms of eczema among children living in different parts of Latin America. Data were from centers that participated in ISAAC Phase 3. METHODS: This was a cross-sectional questionnaire survey of 93,851 schoolchildren (6 to 7 years old) from 35 centers in 14 Latin American countries and 165,917 adolescents (13 to 14 years old) from 56 centers in 17 Latin American countries. RESULTS: The mean prevalence of current flexural eczema in schoolchildren was 11.3%, ranging from 3.2% in Ciudad Victoria (Mexico) to 25.0% in Barranquilla (Colombia). For adolescents, the prevalence varied from 3.4% in Santo André (Brazil) to 30.2% in Barranquilla (mean prevalence, 10.6%). The mean prevalence of current symptoms of severe eczema among schoolchildren was 1.5%, ranging from 0.3% in Ciudad Victoria, Toluca, and Cuernavaca (Mexico) to 4.9% in La Habana (Cuba). For adolescents, the mean prevalence was 1.4%, ranging from 0.1% in Mexicali Valley (Mexico) to 4.2% in Santa Cruz (Bolivia). These prevalence values are among the highest observed during ISAAC Phase 3. In general, the prevalence of current symptoms of eczema was higher among the Spanish-speaking centers for both schoolchildren and adolescents. CONCLUSION: Environmental risk factors must be evaluated in order to identify potential causes for the differences observed, even in centers from the same country.

Common cold decreases lung function in infants with recurrent wheezing.

BACKGROUND: Common acute viral respiratory infections (colds) are the most frequent cause of exacerbations in infants with recurrent wheezing (RW). However, there is no quantitative information about the effect of colds on the lung function of infants with RW. This study was undertaken to determine the effect of common cold on forced expiratory parameters measured from raised lung volume in infants with RW. METHODS: Spirometric lung function (expiratory flows from raised lung volume) was randomly assessed in 28 infants with RW while they had a common cold and when asymptomatic. RESULTS: It was found that during colds there was a significant decrease in all forced expiratory parameters and this was much more evident for flows (FEF(50%), FEF(75%) and FEF(25-75%)) which were definitively abnormal (less than -1.65 z-score) in the majority of infants. There was not association between family asthma, tobacco exposure, and other factors, with the extent of lung function decrease during colds. Tobacco during pregnancy but not a history of family asthma was significantly associated to lower expiratory flows; however, the association was significant only when infants were asymptomatic. CONCLUSION: This study shows that common colds cause a marked reduction of lung function in infants with RW.

Poverty-associated risk factors for wheezing in the first year of life in Honduras and El Salvador.

BACKGROUND: Risk factors for wheezing specifically during the first year of life have been studied in well-developed countries, but the information from developing countries is very scarce. There are no such studies focusing on factors derived from poverty. The aim of the present study was to determine if risk factors related to poverty are associated to wheezing during the first year of life in infants from Honduras and El Salvador. METHODS: A survey, using a validated questionnaire, was carried out in the metropolitan area of San Pedro Sula (Honduras) and in La Libertad (El Salvador) in centres where infants attended for a scheduled vaccination shot or a healthy child visit at 12 months of age. Fieldworkers offered questionnaires to parents and helped the illiterate when necessary. The main outcome variable was wheezing during the first year of life, as reported by parents. RESULTS: A total of 1047 infants in El Salvador and 780 in Honduras were included in the analysis. The prevalence of wheeze in the first year was higher in El Salvador (41.2%) than in Honduras (27.7%), as was recurrent wheezing defined as three or more episodes (18.4% vs. 11.7%). Wheezing and recurrent wheezing was associated to unpaved floor in the household (summary odds ratios for both countries 1.55, p=0.036 and 1.72, p=0.054 for any wheeze and recurrent wheezing, respectively); dust entering from streets (1.30, p=0.052 and 1.67, p=0.008); living in a heavily polluted area (1.33, p=0.037 and 1.52, p=0.033); and having mould stains on the household walls (1.36, p=0.072 and 1.76, p=0.007). Furthermore, marginal associations were found for additional person at home and use of kerosene as cooking fuel. University studies in the mother (0.34, p=0.046 and 0.32, p=0.022) and a professional occupation in the father (0.34, p=0.046 and 0.26, p=0.047) were associated to a lower risk. CONCLUSIONS: The prevalence of wheezing and recurrent wheezing is notoriously high in El Salvador and Honduras. In those populations factors related to poverty are associated to a higher prevalence of wheezing and recurrent wheezing, whereas higher maternal education and paternal professional occupation behave as protective factors.

International Study of Wheezing in Infants (EISL): validation of written questionnaire for children aged below 3 years.

BACKGROUND: The multicenter International Study of Wheezing in Infants (EISL) was developed to study the prevalence of recurrent wheezing and related risk factors in infants during the first year of life using a written questionnaire (EISL-WQ). OBJECTIVES: To constructively validate a modified, shortened version of the EISL-WQ in children up to 36 months of age in São Paulo, Brazil, and to verify its usefulness in diagnosing probable asthma in these children. METHODS: The parents of 170 infants aged 12 to 36 months answered the shortened EISL-WQ in an emergency room and were asked if their child was currently wheezing before a diagnosis was made by a physician. The consistency between parent perception and the physician's diagnosis was then evaluated. A second group (n = 55) participated in the validation of the short-term repeatability of the shortened questionnaire by completing it twice (mean interval, 23 days). RESULTS: There was good agreement between parent perception of wheezing and the physician's diagnosis following auscultation (Kappa statistic = 0.7; odds ratio = 38.33; 95% confidence interval, 15.8 to 92.8; P < .001); sensitivity (82.8%), specificity (85.0%), positive predictive value (81.5%), and negative predictive value (86.0%) were all high.The short-term repeatability of the shortened version of the EISL-WQ was also high (kappa > 0.75). Questions added to the shortened EISL-WQ improved the internal consistency of the original questionnaire (Cronbach alpha = 0.823, P < .001) and a high Youden index was found for patients defined as probable asthmatics. CONCLUSIONS: The shortened version of the EISL-WQ translated into Portuguese has high internal consistency, and is a valid, reliable, and reproducible instrument for obtaining data on wheezing in children below 36 months of age and for identifying those with probable asthma.

Heightened bronchial hyperresponsiveness in the absence of heightened atopy in children with current wheezing and low income status.

BACKGROUND: Although global studies such as the International Study of Asthma and Allergies in Childhood (ISAAC) have provided valuable data on the prevalence of asthma in children in Latin America, there is little information on the relationship between asthma symptoms, pulmonary function, bronchial hyperresponsiveness (BHR) and atopy in the region. METHODS: This study examined the relationship between self-reported wheezing in the past 12 months, pulmonary function, airway responsiveness and atopy in children from a low income population in a neighbourhood of Santiago, Chile. Two random samples (100 each) of children aged 13-14 years who participated in ISAAC phase I were selected according to whether or not they reported wheezing in the past 12 months. Spirometry, the methacholine bronchial challenge test and the prick test were performed in all individuals. RESULTS: Children who reported current wheezing had significantly higher BHR to methacholine compared with those without wheezing (71.6% vs 52.6%; p = 0.007) and no significant difference was found in forced expiratory volume in 1 s (116.7 (12.3)% vs 120.3 (14.5%); p = 0.11). The prevalence of atopy was not significantly different between those children who reported wheezing compared with those who did not (44.2% vs 42.3%; p = 0.89). Multiple regression analysis showed that only BHR to methacholine (OR 2.72, 95% CI 1.25 to 4.13; p = 0.01) and maternal asthma (OR 3.1, 95% CI 1.2 to 8.3, p = 0.03) were significant risk factors for current wheezing. CONCLUSIONS: Our results support previous findings suggesting that in adolescents from underprivileged populations, self-reported current wheezing is related to BHR but not to atopy.

G-protein-coupled receptor heteromers: function and ligand pharmacology.

Almost all existing models for G-protein-coupled receptors (GPCRs) are based on the occurrence of monomers. Recent studies show that many GPCRs are dimers. Therefore for some receptors dimers and not monomers are the main species interacting with hormones/neurotransmitters/drugs. There are reasons for equivocal interpretations of the data fitting to receptor dimers assuming they are monomers. Fitting data using a dimer-based model gives not only the equilibrium dissociation constants for high and low affinity binding to receptor dimers but also a 'cooperativity index' that reflects the molecular communication between monomers within the dimer. The dimer cooperativity index (D(C)) is a valuable tool that enables to interpret and quantify, for instance, the effect of allosteric regulators. For different receptors heteromerization confers a specific functional property for the receptor heteromer that can be considered as a 'dimer fingerprint'. The occurrence of heteromers with different pharmacological and signalling properties opens a complete new field to search for novel drug targets useful to combat a variety of diseases and potentially with fewer side effects. Antagonists, which are quite common marketed drugs targeting GPCRs, display variable affinities when a given receptor is expressed with different heteromeric partners. This fact should be taken into account in the development of new drugs.